This invention provides for a centrifugal fan blade structure or assembly which is capable of producing efficient air flow during use with substantially less noise than is produced by prior centrifugal fans of similar configuration or size. The movement of air into and out of the housings of various units of equipment in use in the work place is done by means of various fans, for the most part. As more and more machines are moved into the work environment, the level of noise created by fans increases substantially. Nevertheless, machines that are used in the modern office, including computer disk drives must maintain adequate air flow for various purposes, in particular but not limited to maintenance of air pressure differentials and air flows. Accordingly, this invention provides a design structure to produce a quiet fan with adequate air flow.
The structural configuration of the preferred embodiment was developed to reduce the noise created by a prior open bladed configuration as is described in more detail below with reference to the preferred embodiment.